A boat drive of this type is described, for example, in European patent document EP 01 54 954, and here the pitch-adjustment command element is a control lever at the operating post of the ship which actuates the hydraulic-adjusting system or its valves.
Since ship drives having a motor and a variable-pitch propeller are sensitive systems which should be operated in as error-free manner as is possible, various control systems have been proposed for them (see German patent document 39 01 137). Such controls have been found to be rather complex and expensive, requiring repair and maintenance only by qualified personnel and in qualified maintenance facilities.